New completion design for low-production oil field under highly
An operator in China had set high-level, 15-year production targets for
a large oil field, where average well production was low. The goals were to
enhance the annual oil production rate while balancing the reserves and
production, and to reach a stable annual gas production rate of 500 million
cubic meters. Due to the low production, recovery was typically enabled by the
use of rod pumps, which were used rather than submersible pumps because of
standard practices in the area and the lower costs.
In selecting the type of completions for this field, the operator had
several constraints. First, the production area was located below an industrial
zone and several cities, so access was limited and interventions would be
Second, the operator's production targets and timeline required an
efficient, economical approach to completing the wells. For these reasons, the
operator chose to use multilateral drilling and completions, even though this
technology was generally considered cost-prohibitive in low-production
environments. Multilaterals would limit the amount of energy required and
improve the production of single wellsites by connecting multiple wellbores to
a single wellhead. The smaller multilateral footprint would reduce the amount
of surface equipment and personnel needed, and lower HSE risks and costs.
A third constraint was related to the rod pumps, which require frequent
workovers for operations such as acid wash, reperforations, and cement squeeze.
It was important to select a multilateral junction that would ensure full
access to each lateral and easy retrieval.